chr18-3141986-G-A

Position:

chr18-3141986-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_003803.4(MYOM1):c.1978C>T(p.Pro660Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000459 in 1,613,530 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P660A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000049 ( 0 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 10.0

Variant links:

Genes affected

MYOM1 (HGNC:7613): (myomesin 1) The giant protein titin, together with its associated proteins, interconnects the major structure of sarcomeres, the M bands and Z discs. The C-terminal end of the titin string extends into the M line, where it binds tightly to M-band constituents of apparent molecular masses of 190 kD (myomesin 1) and 165 kD (myomesin 2). This protein, myomesin 1, like myomesin 2, titin, and other myofibrillar proteins contains structural modules with strong homology to either fibronectin type III (motif I) or immunoglobulin C2 (motif II) domains. Myomesin 1 and myomesin 2 each have a unique N-terminal region followed by 12 modules of motif I or motif II, in the arrangement II-II-I-I-I-I-I-II-II-II-II-II. The two proteins share 50% sequence identity in this repeat-containing region. The head structure formed by these 2 proteins on one end of the titin string extends into the center of the M band. The integrating structure of the sarcomere arises from muscle-specific members of the superfamily of immunoglobulin-like proteins. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

MYOM1 links:

MYOM1 (HGNC:):

MYOM1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.833

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYOM1	NM_003803.4 linkuse as main transcript	c.1978C>T	p.Pro660Ser	missense_variant	14/38	ENST00000356443.9	NP_003794.3	P52179-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
MYOM1	ENST00000356443.9 linkuse as main transcript	c.1978C>T	p.Pro660Ser	missense_variant	14/38	1	NM_003803.4	ENSP00000348821.4	P52179-1
MYOM1	ENST00000261606.11 linkuse as main transcript	c.1978C>T	p.Pro660Ser	missense_variant	14/37	1		ENSP00000261606.7	P52179-2
MYOM1	ENST00000577294.1 linkuse as main transcript	n.34C>T		non_coding_transcript_exon_variant	1/2	2

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151944

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.000956

GnomAD3 exomes

AF:

0.0000321

AC:

AN:

249188

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

135188

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000620

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.0000493

AC:

AN:

1461586

Hom.:

Cov.:

AF XY:

0.0000536

AC XY:

AN XY:

727086

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000549

Gnomad4 OTH exome

AF:

0.000166

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151944

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74196

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000956

Alfa

AF:

0.00000873

Hom.:

ExAC

AF:

0.0000414

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Hypertrophic cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 25, 2021

This sequence change replaces proline with serine at codon 660 of the MYOM1 protein (p.Pro660Ser). The proline residue is moderately conserved and there is a moderate physicochemical difference between proline and serine. This variant is present in population databases (rs201104206, ExAC 0.005%). This variant has not been reported in the literature in individuals affected with MYOM1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.31

BayesDel_addAF

Uncertain

0.041

BayesDel_noAF

Uncertain

0.0

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.21

T;.;.

Eigen

Pathogenic

0.92

Eigen_PC

Pathogenic

0.88

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.98

D;D;D

M_CAP

Benign

0.073

MetaRNN

Pathogenic

0.83

D;D;D

MetaSVM

Uncertain

-0.19

MutationAssessor

Uncertain

2.3

M;.;M

PrimateAI

Benign

0.47

PROVEAN

Pathogenic

-5.3

D;.;D

REVEL

Uncertain

0.55

Sift

Uncertain

0.0030

D;.;D

Sift4G

Uncertain

0.0090

D;D;D

Polyphen

1.0

D;.;D

Vest4

0.81

MutPred

0.59

Loss of catalytic residue at P660 (P = 0.0055);.;Loss of catalytic residue at P660 (P = 0.0055);

MVP

0.85

MPC

0.63

ClinPred

0.90

GERP RS

5.9

Varity_R

0.54

gMVP

0.62

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over